struct dirty_throttle_control *gdtc = mdtc_gdtc(dtc);
unsigned long bytes = vm_dirty_bytes;
unsigned long bg_bytes = dirty_background_bytes;
- unsigned long ratio = vm_dirty_ratio;
- unsigned long bg_ratio = dirty_background_ratio;
+ /* convert ratios to per-PAGE_SIZE for higher precision */
+ unsigned long ratio = (vm_dirty_ratio * PAGE_SIZE) / 100;
+ unsigned long bg_ratio = (dirty_background_ratio * PAGE_SIZE) / 100;
unsigned long thresh;
unsigned long bg_thresh;
struct task_struct *tsk;
/*
* The byte settings can't be applied directly to memcg
* domains. Convert them to ratios by scaling against
- * globally available memory.
+ * globally available memory. As the ratios are in
+ * per-PAGE_SIZE, they can be obtained by dividing bytes by
+ * number of pages.
*/
if (bytes)
- ratio = min(DIV_ROUND_UP(bytes, PAGE_SIZE) * 100 /
- global_avail, 100UL);
+ ratio = min(DIV_ROUND_UP(bytes, global_avail),
+ PAGE_SIZE);
if (bg_bytes)
- bg_ratio = min(DIV_ROUND_UP(bg_bytes, PAGE_SIZE) * 100 /
- global_avail, 100UL);
+ bg_ratio = min(DIV_ROUND_UP(bg_bytes, global_avail),
+ PAGE_SIZE);
bytes = bg_bytes = 0;
}
if (bytes)
thresh = DIV_ROUND_UP(bytes, PAGE_SIZE);
else
- thresh = (ratio * available_memory) / 100;
+ thresh = (ratio * available_memory) / PAGE_SIZE;
if (bg_bytes)
bg_thresh = DIV_ROUND_UP(bg_bytes, PAGE_SIZE);
else
- bg_thresh = (bg_ratio * available_memory) / 100;
+ bg_thresh = (bg_ratio * available_memory) / PAGE_SIZE;
if (bg_thresh >= thresh)
bg_thresh = thresh / 2;
__wb_writeout_inc(wb);
}
}
+
+ if (mapping->host && !mapping_tagged(mapping,
+ PAGECACHE_TAG_WRITEBACK))
+ sb_clear_inode_writeback(mapping->host);
+
spin_unlock_irqrestore(&mapping->tree_lock, flags);
} else {
ret = TestClearPageWriteback(page);
spin_lock_irqsave(&mapping->tree_lock, flags);
ret = TestSetPageWriteback(page);
if (!ret) {
+ bool on_wblist;
+
+ on_wblist = mapping_tagged(mapping,
+ PAGECACHE_TAG_WRITEBACK);
+
radix_tree_tag_set(&mapping->page_tree,
page_index(page),
PAGECACHE_TAG_WRITEBACK);
if (bdi_cap_account_writeback(bdi))
__inc_wb_stat(inode_to_wb(inode), WB_WRITEBACK);
+
+ /*
+ * We can come through here when swapping anonymous
+ * pages, so we don't necessarily have an inode to track
+ * for sync.
+ */
+ if (mapping->host && !on_wblist)
+ sb_mark_inode_writeback(mapping->host);
}
if (!PageDirty(page))
radix_tree_tag_clear(&mapping->page_tree,